Still "out of memory" error

Today I experienced an other crash of FSX (BTW this time no related error report, last time it was pointing to PMDG_737NGX.dll). Flight from EHAM to EDDT, the crash happened just after leaving Rwy 27 and turning left in order to take course to EDDT, before reaching 6000ft. I'm running Win7x64 on quite nice hardware being rock stable up to now: My rig:ASUS P8Z68-V, i7-2600K CPU @ 3.40GHz, Noctua NH-12P SE2 and 16 GB Kingston RAM,GPU: AMD HD 5870, 1024 MB,BE Quiet Dark Power Pro 650W,Antec 801 case with 3 fans. After the crash the FSX had eaten about 2.4GByte of memory (error message still open) and the rest was much less important. In parallel ASE and FS Commander worked and before it happened no sign of irregularities. Funny, as written before, I did not find any event fitting to the case in my log files. Ah, yes the fix is installed. It happened to the 800WL and I was able to continue the flight after recovering it via FSUIPC without any problem. Any ideas? Regards,Axel (who wrote an error report to PMDG, off course)